The subject matter disclosed herein relates to aircraft. More specifically, the subject disclosure relates to fuel bladder structures for aircraft.
Aircraft, such as airplanes, helicopters, turbo props and tilt rotor aircraft typically often include one or more flexible containers, or bladders, for storage of fuel on board the aircraft. The bladder provides a sealed volume for the storage of fuel as an alternative to forming a sealed chamber in the aircraft structure. Mounting the bladder in such a chamber is typically difficult and costly. The bladders include fittings and/or connections for filling the bladder with fuel, outputting the fuel to an aircraft engine, and may also include ancillary components such as fuel pumps and fuel filters and vent fittings.
In a typical aircraft, most often a helicopter, the bladders are contained in sponsons, or projections from the fuselage of the aircraft. As such, the fuel bladders are contained in a space external to the fuselage and do not negatively impact cargo or passenger space in the aircraft. Further, the external location allows for easy access for installation and mounting of the fuel bladders into the sponsons.
The fuel bladder further must include crashworthiness features to prevent leakage of the fuel bladder in the case of fuel cell tear away, hose/device pull out, structure separation or other occurrence preventing fuel from spilling into the cockpit and/or passenger compartment. Embedding the fuel bladder into the fuselage presents unique challenges to fulfilling this requirement.